Chakra nature, in the NV, refers to the five basic elements in which shinobi use for combat; and these elements are Earth, Wind, Fire, Lightining & Water. All natures have strengths and weaknesses [Fire→Wind→Lightning→Earth→Water→Fire, etc]. Rarely, a ninja's KG/KT allows them to combine two or three elements together to create a new one (ex. Ice, Storm).
Shape manipulation is used to control the form of nature chakra and its physical properties (ex. Turning earth chakra into mud; turning water chakra into a wave or a stream).
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- Suiton is strongest against fire, or Katon. This is because [like in the real world] water smothers the flame or in other words prevents the fire from taking in oxygen, which they need to burn.
- Suiton is weak to Doton because it's structure is able to resist or withstand the fluid nature of water. However, this is not always the case as certain water techniques that are meant for hardening/slicing are capable of cutting away doton techniques.
- Mokuton [wood] release is created by "fusing" together Suiton & Doton. Hyouton [ice] release is formed through the simultaneous usage of Suiton & Futon. Ranton [storm] release is generated by using Raiton & Suiton. Futton [boil] release is made by combining Suiton & Katon together.